Tread portion of an automobile tire



FIG. 1 is a perspective view of a tread portion of an automobile tire showing my design;

FIG. 2 is a front view thereof;

FIG. 3 is a top view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a fragmentary enlarged front view showing the details of the tread portion thereof; and,

FIG. 6 is a section view taken along line 6-6 in FIG. 5.

The broken lines show portions of the tire that are not being claimed, and thus form no part of the claimed design. 

CLAIM The ornamental design for a tread portion of an automobile tire, as shown and described. 